masakari/masakari/engine/drivers/taskflow/host_failure.py

527 lines
22 KiB
Python

# Copyright 2016 NTT DATA
# All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.
import eventlet
from eventlet import greenpool
from oslo_config import cfg
from oslo_log import log as logging
from oslo_service import loopingcall
from oslo_utils import excutils
from oslo_utils import strutils
from oslo_utils import timeutils
from taskflow.patterns import linear_flow
from taskflow import retry
import masakari.conf
from masakari.engine.drivers.taskflow import base
from masakari import exception
from masakari import objects
from masakari.objects import fields
from masakari import utils
CONF = masakari.conf.CONF
LOG = logging.getLogger(__name__)
ACTION = 'instance:evacuate'
# Instance power_state
SHUTDOWN = 4
TASKFLOW_CONF = cfg.CONF.taskflow_driver_recovery_flows
class DisableComputeServiceTask(base.MasakariTask):
def __init__(self, context, novaclient, **kwargs):
kwargs['requires'] = ["host_name"]
super(DisableComputeServiceTask, self).__init__(context, novaclient,
**kwargs)
def execute(self, host_name):
msg = "Disabling compute service on host: '%s'" % host_name
self.update_details(msg)
self.novaclient.enable_disable_service(self.context, host_name,
reason=CONF.host_failure.service_disable_reason)
# Sleep until nova-compute service is marked as disabled.
log_msg = ("Sleeping %(wait)s sec before starting recovery "
"thread until nova recognizes the node down.")
LOG.info(log_msg, {'wait': CONF.wait_period_after_service_update})
eventlet.sleep(CONF.wait_period_after_service_update)
msg = "Disabled compute service on host: '%s'" % host_name
self.update_details(msg, 1.0)
class PrepareHAEnabledInstancesTask(base.MasakariTask):
"""Get all HA_Enabled instances."""
def __init__(self, context, novaclient, **kwargs):
kwargs['requires'] = ["host_name", "notification_uuid"]
super(PrepareHAEnabledInstancesTask, self).__init__(context,
novaclient,
**kwargs)
def execute(self, host_name, notification_uuid):
def _filter_instances(instance_list):
ha_enabled_instances = []
non_ha_enabled_instances = []
ha_enabled_key = CONF.host_failure.ha_enabled_instance_metadata_key
for instance in instance_list:
is_instance_ha_enabled = strutils.bool_from_string(
instance.metadata.get(ha_enabled_key, False))
if CONF.host_failure.ignore_instances_in_error_state and (
getattr(instance, "OS-EXT-STS:vm_state") == "error"):
if is_instance_ha_enabled:
msg = ("Ignoring recovery of HA_Enabled instance "
"'%(instance_id)s' as it is in 'error' state."
) % {'instance_id': instance.id}
LOG.info(msg)
self.update_details(msg, 0.4)
continue
if is_instance_ha_enabled:
ha_enabled_instances.append(instance)
else:
non_ha_enabled_instances.append(instance)
msg = "Total HA Enabled instances count: '%d'" % len(
ha_enabled_instances)
self.update_details(msg, 0.6)
if CONF.host_failure.evacuate_all_instances:
msg = ("Total Non-HA Enabled instances count: '%d'" % len(
non_ha_enabled_instances))
self.update_details(msg, 0.7)
ha_enabled_instances.extend(non_ha_enabled_instances)
msg = ("All instances (HA Enabled/Non-HA Enabled) should be "
"considered for evacuation. Total count is: '%d'") % (
len(ha_enabled_instances))
self.update_details(msg, 0.8)
return ha_enabled_instances
msg = "Preparing instances for evacuation"
self.update_details(msg)
instance_list = self.novaclient.get_servers(self.context, host_name)
msg = ("Total instances running on failed host '%(host_name)s' is "
"%(instance_list)d") % {'host_name': host_name,
'instance_list': len(instance_list)}
self.update_details(msg, 0.3)
instance_list = _filter_instances(instance_list)
if not instance_list:
msg = ("Skipped host '%s' recovery as no instances needs to be "
"evacuated" % host_name)
self.update_details(msg, 1.0)
LOG.info(msg)
raise exception.SkipHostRecoveryException(message=msg)
# persist vm moves
for instance in instance_list:
vmove = objects.VMove(context=self.context)
vmove.instance_uuid = instance.id
vmove.instance_name = instance.name
vmove.notification_uuid = notification_uuid
vmove.source_host = host_name
vmove.status = fields.VMoveStatus.PENDING
vmove.type = fields.VMoveType.EVACUATION
vmove.create()
# List of instance UUID
instance_list = [instance.id for instance in instance_list]
msg = "Instances to be evacuated are: '%s'" % ','.join(instance_list)
self.update_details(msg, 1.0)
class EvacuateInstancesTask(base.MasakariTask):
def __init__(self, context, novaclient, **kwargs):
kwargs['requires'] = ["host_name", "notification_uuid"]
self.update_host_method = kwargs['update_host_method']
super(EvacuateInstancesTask, self).__init__(context, novaclient,
**kwargs)
def _get_state_and_host_of_instance(self, context, instance):
new_instance = self.novaclient.get_server(context, instance.id)
instance_host = getattr(new_instance,
"OS-EXT-SRV-ATTR:hypervisor_hostname")
old_vm_state = getattr(instance, "OS-EXT-STS:vm_state")
new_vm_state = getattr(new_instance, "OS-EXT-STS:vm_state")
return (old_vm_state, new_vm_state, instance_host)
def _stop_after_evacuation(self, context, instance):
def _wait_for_stop_confirmation():
old_vm_state, new_vm_state, instance_host = (
self._get_state_and_host_of_instance(context, instance))
if new_vm_state == 'stopped':
raise loopingcall.LoopingCallDone()
try:
# confirm instance is stopped after recovery
self.novaclient.stop_server(context, instance.id)
timer = loopingcall.FixedIntervalWithTimeoutLoopingCall(
_wait_for_stop_confirmation)
timer.start(interval=CONF.verify_interval,
timeout=CONF.wait_period_after_power_off).wait()
except loopingcall.LoopingCallTimeOut:
with excutils.save_and_reraise_exception():
msg = ("Instance '%(uuid)s' is successfully evacuated but "
"timeout to stop.") % {'uuid': instance.id}
LOG.warning(msg)
finally:
timer.stop()
def _evacuate_and_confirm(self, context, vmove,
reserved_host=None):
def _update_vmove(vmove, status=None, start_time=None,
end_time=None, dest_host=None,
message=None):
if status:
vmove.status = status
if start_time:
vmove.start_time = start_time
if end_time:
vmove.end_time = end_time
if dest_host:
vmove.dest_host = dest_host
if message:
vmove.message = message
vmove.save()
instance_uuid = vmove.instance_uuid
instance = self.novaclient.get_server(context, instance_uuid)
# Before locking the instance check whether it is already locked
# by user, if yes don't lock the instance
instance_already_locked = self.novaclient.get_server(
context, instance.id).locked
if not instance_already_locked:
# lock the instance so that until evacuation and confirmation
# is not complete, user won't be able to perform any actions
# on the instance.
self.novaclient.lock_server(context, instance.id)
def _wait_for_evacuation_confirmation():
old_vm_state, new_vm_state, instance_host = (
self._get_state_and_host_of_instance(context, instance))
if (new_vm_state == 'error' and
new_vm_state != old_vm_state):
raise exception.InstanceEvacuateFailed(
instance_uuid=instance.id)
if instance_host != vmove.source_host:
if ((old_vm_state == 'error' and
new_vm_state == 'active') or
old_vm_state == new_vm_state):
raise loopingcall.LoopingCallDone()
def _wait_for_evacuation():
try:
# add a timeout to the periodic call.
timer = loopingcall.FixedIntervalWithTimeoutLoopingCall(
_wait_for_evacuation_confirmation)
timer.start(interval=CONF.verify_interval,
timeout=CONF.wait_period_after_evacuation).wait()
except loopingcall.LoopingCallTimeOut:
with excutils.save_and_reraise_exception():
msg = ("Timeout for instance '%(uuid)s' evacuation."
% {'uuid': instance.id})
LOG.warning(msg)
finally:
# stop the periodic call, in case of exceptions or
# Timeout.
timer.stop()
try:
vm_state = getattr(instance, "OS-EXT-STS:vm_state")
task_state = getattr(instance, "OS-EXT-STS:task_state")
# Nova evacuates an instance only when vm_state is in active,
# stopped or error state. If an instance is in other than active,
# error and stopped vm_state, masakari resets the instance state
# to *error* so that the instance can be evacuated.
stop_instance = True
if vm_state not in ['active', 'error', 'stopped']:
self.novaclient.reset_instance_state(context, instance.id)
instance = self.novaclient.get_server(context, instance.id)
power_state = getattr(instance, "OS-EXT-STS:power_state")
if vm_state == 'resized' and power_state != SHUTDOWN:
stop_instance = False
elif vm_state == 'stopped' and task_state is None:
# If vm_state is stopped and task_state is none, the instance
# will be recovered with vm_state 'stopped'.
# So it doesn't need to stop the instance after evacuation.
stop_instance = False
elif task_state is not None:
# Nova fails evacuation when the instance's task_state is not
# none. In this case, masakari resets the instance's vm_state
# to 'error' and task_state to none.
self.novaclient.reset_instance_state(context, instance.id)
instance = self.novaclient.get_server(context, instance.id)
if vm_state == 'active':
stop_instance = False
# start to evacuate the instance
_update_vmove(
vmove,
status=fields.VMoveStatus.ONGOING,
start_time=timeutils.utcnow())
self.novaclient.evacuate_instance(context, instance.id,
target=reserved_host)
_wait_for_evacuation()
if vm_state != 'active':
if stop_instance:
self._stop_after_evacuation(self.context, instance)
# If the instance was in 'error' state before failure
# it should be set to 'error' after recovery.
if vm_state == 'error':
self.novaclient.reset_instance_state(
context, instance.id)
instance = self.novaclient.get_server(context, instance_uuid)
dest_host = getattr(
instance, "OS-EXT-SRV-ATTR:hypervisor_hostname")
_update_vmove(
vmove,
status=fields.VMoveStatus.SUCCEEDED,
dest_host=dest_host)
except loopingcall.LoopingCallTimeOut:
# Instance is not stop in the expected time_limit.
msg = "Failed reason: timeout."
_update_vmove(
vmove,
status=fields.VMoveStatus.FAILED,
message=msg)
except Exception as e:
# Exception is raised while resetting instance state or
# evacuating the instance itself.
LOG.warning(str(e))
_update_vmove(
vmove,
status=fields.VMoveStatus.FAILED,
message=str(e))
finally:
_update_vmove(vmove, end_time=timeutils.utcnow())
if not instance_already_locked:
# Unlock the server after evacuation and confirmation
self.novaclient.unlock_server(context, instance.id)
def execute(self, host_name, notification_uuid, reserved_host=None):
all_vmoves = objects.VMoveList.get_all_vmoves(
self.context, notification_uuid, status=fields.VMoveStatus.PENDING)
instance_list = [i.instance_uuid for i in all_vmoves]
msg = ("Start evacuation of instances from failed host '%(host_name)s'"
", instance uuids are: '%(instance_list)s'") % {
'host_name': host_name, 'instance_list': ','.join(instance_list)}
self.update_details(msg)
def _do_evacuate(context, host_name,
reserved_host=None):
if reserved_host:
msg = "Enabling reserved host: '%s'" % reserved_host
self.update_details(msg, 0.1)
if CONF.host_failure.add_reserved_host_to_aggregate:
# Assign reserved_host to an aggregate to which the failed
# compute host belongs to.
aggregates = self.novaclient.get_aggregate_list(context)
for aggregate in aggregates:
if host_name in aggregate.hosts:
try:
msg = ("Add host %(reserved_host)s to "
"aggregate %(aggregate)s") % {
'reserved_host': reserved_host,
'aggregate': aggregate.name}
self.update_details(msg, 0.2)
self.novaclient.add_host_to_aggregate(
context, reserved_host, aggregate)
msg = ("Added host %(reserved_host)s to "
"aggregate %(aggregate)s") % {
'reserved_host': reserved_host,
'aggregate': aggregate.name}
self.update_details(msg, 0.3)
except exception.Conflict:
msg = ("Host '%(reserved_host)s' already has "
"been added to aggregate "
"'%(aggregate)s'.") % {
'reserved_host': reserved_host,
'aggregate': aggregate.name}
self.update_details(msg, 1.0)
LOG.info(msg)
self.novaclient.enable_disable_service(
context, reserved_host, enable=True)
# Set reserved property of reserved_host to False
self.update_host_method(context, reserved_host)
thread_pool = greenpool.GreenPool(
CONF.host_failure_recovery_threads)
nonlocal all_vmoves
for vmove in all_vmoves:
msg = ("Evacuation of instance started: '%s'"
% vmove.instance_uuid)
self.update_details(msg, 0.5)
thread_pool.spawn_n(self._evacuate_and_confirm, self.context,
vmove, reserved_host)
thread_pool.waitall()
all_vmoves = objects.VMoveList.get_all_vmoves(
self.context, notification_uuid)
succeeded_vmoves = [i.instance_uuid for i in all_vmoves
if i.status == fields.VMoveStatus.SUCCEEDED]
if succeeded_vmoves:
succeeded_vmoves.sort()
msg = ("Successfully evacuate instances '%(instance_list)s' "
"from host '%(host_name)s'") % {
'instance_list': ','.join(succeeded_vmoves),
'host_name': host_name}
self.update_details(msg, 0.7)
failed_vmoves = [i.instance_uuid for i in
all_vmoves if i.status == fields.VMoveStatus.FAILED]
if failed_vmoves:
msg = ("Failed to evacuate instances "
"'%(instance_list)s' from host "
"'%(host_name)s'") % {
'instance_list': ','.join(failed_vmoves),
'host_name': host_name}
self.update_details(msg, 0.7)
raise exception.HostRecoveryFailureException(
message=msg)
msg = "Evacuation process completed!"
self.update_details(msg, 1.0)
lock_name = reserved_host if reserved_host else None
@utils.synchronized(lock_name)
def do_evacuate_with_reserved_host(context, host_name,
notification_uuid, reserved_host):
_do_evacuate(context, host_name,
reserved_host=reserved_host)
if lock_name:
do_evacuate_with_reserved_host(self.context, host_name,
notification_uuid,
reserved_host)
else:
# No need to acquire lock on reserved_host when recovery_method is
# 'auto' as the selection of compute host will be decided by nova.
_do_evacuate(self.context, host_name)
def get_auto_flow(context, novaclient, process_what):
"""Constructs and returns the engine entrypoint flow.
This flow will do the following:
1. Disable compute service on source host
2. Get all HA_Enabled instances.
3. Evacuate all the HA_Enabled instances.
4. Confirm evacuation of instances.
"""
flow_name = ACTION.replace(":", "_") + "_engine"
nested_flow = linear_flow.Flow(flow_name)
task_dict = TASKFLOW_CONF.host_auto_failure_recovery_tasks
auto_evacuate_flow_pre = linear_flow.Flow('pre_tasks')
for plugin in base.get_recovery_flow(task_dict['pre'], context=context,
novaclient=novaclient,
update_host_method=None):
auto_evacuate_flow_pre.add(plugin)
auto_evacuate_flow_main = linear_flow.Flow('main_tasks')
for plugin in base.get_recovery_flow(task_dict['main'], context=context,
novaclient=novaclient,
update_host_method=None):
auto_evacuate_flow_main.add(plugin)
auto_evacuate_flow_post = linear_flow.Flow('post_tasks')
for plugin in base.get_recovery_flow(task_dict['post'], context=context,
novaclient=novaclient,
update_host_method=None):
auto_evacuate_flow_post.add(plugin)
nested_flow.add(auto_evacuate_flow_pre)
nested_flow.add(auto_evacuate_flow_main)
nested_flow.add(auto_evacuate_flow_post)
return base.load_taskflow_into_engine(ACTION, nested_flow,
process_what)
def get_rh_flow(context, novaclient, process_what, **kwargs):
"""Constructs and returns the engine entrypoint flow.
This flow will do the following:
1. Disable compute service on source host
2. Get all HA_Enabled instances.
3. Evacuate all the HA_Enabled instances using reserved_host.
4. Confirm evacuation of instances.
"""
flow_name = ACTION.replace(":", "_") + "_engine"
nested_flow = linear_flow.Flow(flow_name)
task_dict = TASKFLOW_CONF.host_rh_failure_recovery_tasks
rh_evacuate_flow_pre = linear_flow.Flow('pre_tasks')
for plugin in base.get_recovery_flow(
task_dict['pre'],
context=context, novaclient=novaclient, **kwargs):
rh_evacuate_flow_pre.add(plugin)
rh_evacuate_flow_main = linear_flow.Flow(
"retry_%s" % flow_name, retry=retry.ParameterizedForEach(
rebind=['reserved_host_list'], provides='reserved_host'))
for plugin in base.get_recovery_flow(
task_dict['main'],
context=context, novaclient=novaclient, **kwargs):
rh_evacuate_flow_main.add(plugin)
rh_evacuate_flow_post = linear_flow.Flow('post_tasks')
for plugin in base.get_recovery_flow(
task_dict['post'],
context=context, novaclient=novaclient, **kwargs):
rh_evacuate_flow_post.add(plugin)
nested_flow.add(rh_evacuate_flow_pre)
nested_flow.add(rh_evacuate_flow_main)
nested_flow.add(rh_evacuate_flow_post)
return base.load_taskflow_into_engine(ACTION, nested_flow,
process_what)